Department of Internal Medicine, Daegu Catholic University Medical Center, Daegu Catholic University School of Medicine, 33, Duryugongwon-ro 17-gil, Nam-gu, Daegu, 42472, South Korea.
Department of Laboratory Medicine, Daegu Catholic University Medical Center, Daegu Catholic University School of Medicine, Daegu, South Korea.
BMC Pulm Med. 2021 Oct 29;21(1):336. doi: 10.1186/s12890-021-01707-z.
Organizing pneumonia (OP) can be diagnosed pathologically, and cryptogenic OP (COP) and secondary OP (SOP) have been classified by cause and particular underlying context. Because it is clinically difficult to differentiate between COP and SOP, this study investigated characteristics that could distinguish between COP and SOP.
The medical records of patients who underwent lung biopsy for a diagnosis of OP at a single tertiary hospital from January 2016 to December 2018 were retrospectively reviewed.
Eighty-five patients had pathologically proven OP, including 16 diagnosed with COP and 69 diagnosed with SOP. The most common cause of SOP was infectious pneumonia, observed in 57 (82.6%) of the 69 patients, followed by cancer and radiation pneumonitis. The pathogens causing infectious pneumonia were identified in 45 (65.2%) patients. There were no differences in age, sex, and lung function between the COP and SOP groups. Median body mass index was significantly lower (P = 0.030), and median time from symptom onset to hospital admission significantly shorter (P = 0.006), in the SOP than in the COP group. Fever was more common in the SOP group (P = 0.024), and CURB 65, an index of pneumonia severity, tended to be higher in the SOP group (P = 0.017). Some laboratory results differed significantly between the two groups. Lymphocyte counts in bronchoalveolar lavage (BAL) fluid were significantly higher in the COP than in the SOP group (P = 0.012). Radiologic findings showed that effusion was more common in the SOP group (P = 0.036). There were no between-group differences in steroid use, 30 day and in-hospital mortality rates, and rates of OP outcomes and recurrences. Pneumonia recurrence rate was significantly higher in SOP patients who were than were not treated with steroids (P = 0.035).
Infection is the main cause of SOP. Symptom onset is more rapid in patients with SOP than with COP. Some blood and BAL fluid test results differed significantly in the COP and SOP groups. Pleural effusion was more common in the SOP group but there were no differences in clinical course. Recurrence in patients with SOP was more common in those who were than were not treated with steroids.
机化性肺炎（OP）可通过病理诊断，根据病因和特定的潜在背景，将隐源性 OP（COP）和继发性 OP（SOP）进行分类。由于临床上难以区分 COP 和 SOP，本研究旨在探讨有助于鉴别两者的特征。
回顾性分析 2016 年 1 月至 2018 年 12 月在一家三级医院因 OP 行肺活检的患者的病历资料。
85 例患者经病理证实为 OP，其中 16 例诊断为 COP，69 例诊断为 SOP。SOP 最常见的病因是感染性肺炎，在 69 例患者中，57 例（82.6%）由其引起，其次是癌症和放射性肺炎。45 例（65.2%）感染性肺炎患者确定了病原体。COP 和 SOP 组在年龄、性别和肺功能方面无差异。SOP 组的中位体质指数显著较低（P=0.030），且从症状出现到住院的中位时间显著缩短（P=0.006）。SOP 组发热更为常见（P=0.024），肺炎严重程度的 CURB 65 指数也更高（P=0.017）。两组间一些实验室结果存在显著差异。BAL 液中的淋巴细胞计数在 COP 组显著高于 SOP 组（P=0.012）。影像学表现显示 SOP 组胸腔积液更为常见（P=0.036）。两组间激素使用、30 天和住院死亡率以及 OP 结局和复发率无差异。接受激素治疗的 SOP 患者的肺炎复发率显著高于未接受激素治疗的患者（P=0.035）。
感染是 SOP 的主要病因。SOP 患者的症状出现更为迅速。COP 和 SOP 组的一些血液和 BAL 液检测结果存在显著差异。SOP 组胸腔积液更为常见，但临床病程无差异。SOP 患者复发率在接受激素治疗的患者中更高。
